What is 87?

87 is a two-digit odd number that comes after 86 and before 88. In Roman numerals, 87 is written as LXXXVII. It is a prime number, meaning it is only divisible by 1 and itself. The sum of the digits in 87 is 15, and its digit reversal is 78. In binary code, 87 equals 1010111. 87 is also the atomic number of francium, a highly reactive metallic element. In the United States, Interstate 87 is a highway that runs from New York City to the Canadian border.